Automatic contbol device



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AUTOMATIC CONTROL DEVICE. APPLICATION FILED MAR. 13, I918.

1,312,244. Patented Aug. 5,1919.

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0. L. FORTIER.

AUTOMATIC CONTROL DEVICE.

APPLICATION FILED MAR. I8. 1913.

Patent-ed Aug. 5, 1919.

2 SHEETS-SHEET 2.

TIIE coLummA ILANIIGRAPH 20 WASHINGTON, n. c.

CHARLES L. FDRTIER, or MILWAUKEE, Wisconsin.

AUTOMATIC conrnon nnvrcn. I

To all whom it may concern: 1

Be it known that I, CHARLES L. Fon'rmn,

a citizen of the UnitedStates, residing at Milwaukee, in the county ofMilwaukee and tate of Wisconsin, have invented certain new and usefulImprovements in Automatic Control Devices, of which the following is aspecification. y

This invention relates to that type of thermostatic and hygrostaticcontrol devices which employ a movable leak port tube or nozzle to ventthe pressure fluid from the controlled motor or device. Instruments ofthis character are set forth in Patent No. 1,162,170 granted to Carl F.Johnson and dated November 30, 1915. 1

3y later improvements made by said Carl F. Johnson, a wider range ofmovement of the leak port tube or nozzle" has been rendered practicable,and this is quite desirable for many uses of the control mechanism; Suchmechanisms, however, usually employ a bimetallic bar to respond to theatmospheric changes, and to carry the valvepad or closure which sealsand unseals the leak port and initiates the action of the controlmechanism. The radius of the bimetallic element is made relatively shortin order to keep the mechanism within comparatively and the valve padhence does not, in all adjustments of the instru-V small dimensions,

ment, seat squarely against the enclor perpendicular to the axis of theleak port tube or nozzle, and hence may not always seal said portcompletely. This is particularly true when the instrumentiis adjusted toafford a relatively wide range of movement of the leak port tube ornozzle and of the pad or valve-carrier.

The object of the present invention is to provide means for insuring theproper seatingof the valve on the leak port member, in

both the out and in ositions of said member, and thus to enable theinstrument to work efliciently and certainly over a considerable andvariable range of temperature,

This result I attain, preferably, by mounting the sealing valve upontheleak port tube or nozzle so astomove bodilytherewith, and causing thethermostat orvother fiecification of Letters Patent. Applicationfiledltfarcli 18, 1918,

Serial 110,223,153. 1

element responsive to atmospheric condi-Y tions toact uponsaid sealingvalve through intermediate devices, so that the valve may always seatsquarely and perfectly, unaf fected in this regard by varying angularityof the actuating lever or element, or by vary ing range of movementthereof. e

I here illustrate theinventionas applied to the control of temperature,and in an instrument of thegeneral character set forth in Letters PatentNo. 1,109,913 dated Sep tember 8, 1914, or No, 1,212,042 dated January9, 1917, both granted to me. In the chosen illustration, however, I showof thermostat suitable for insertion vapor, and of the direct expansiontype,

though my improvements are applicable in connection with various typesof thermostats and hygrostats; so, too, the pad, valve, or closure mayin some cases be car Patented Aug. 5,

a form lnto a tank or chamber containingllquichgas, or

ried by a lever pivotally supported upon the fixed frame oftheinstrument, together with p the adjusting devices for said lever,

Referring now to the accompanying draw lugs: i e

Figure l is a side elevationof a thermostatic control device embodyingmy ind provements;

Fig. 2 1s a frontelevation thereof,

Fig. 3 is asimilar view with parts broken away or in section to showparts that would otherwise be hidden;

Fig. 4f isja sectional view of theleakport tube or nozzle, the motor bywhich it is advanced and receded, and thevalve or closure which sealsand unseals the leak port in response to changing atmosphericconditions,

the parts being shown in sealing position;

Fig. 5 is a similar View but with the parts i in unsealing relation;

Fig. 6 is a front face View of the same parts, showing the adjustingdisk or head of the stop with its scale and pointer;

Fig. 7 is a view similar to F ig; 2, but showing the lever or armcarrying the sealing valve or closure for the leak port, otedlto theframe of the thermostat.

The construction and operation of thedevice may be best explained withthesaid of Fig. 3, wherein 1 indicates a tube of brass, copper, orothersubstance having a relatively high coefficient of expansion, and 2 a rodof some substance having a lower coefficient of expansion. The rear orinner end oftube l is closed by a cap 3, and the corresponding end ofrod 2 is held in contact with its cap or closure by a spring 4:, bearingat its inner endagainst the radial flange of a cap sleeve 2 applied tothe outer end of rod 2, and at its outer end against the inner wall of acombined cap-plate and bracket 12 secured to the frontofthe main frame,base or support 5 of the structure. The base or support 5 is formed witha tubular rearward extension-5 which receivesor forms a pipe head forthe tube 1', saidextension being exteIiOrly threaded at its end to screwinto thewall of a tank or vessel, and provided with a polygonal portionto receive a wrench or like toolfor' screwing it to place.

As shown in Fig.- 2, base or support 5 is formed with internallythreaded bosses 7 and 8to receive pipes, the former being connected toan accumulator or pressurefluid supply, and the latter to a valve ordevice tobe controlled, as in the apparatus of the well-known Johnsonsystem of temperature control. 6 indicates a casting which is secured byscrews9 and 10-or other fastenings to the base 5, an air-tight jointbetween them'being insured by interposing a gasket 11 of leather,rubber, or other suitable material. j(See Fig. 3). p

-Hin'g'e'd or pivoted tobracket 12 is an upstanding lever 13, here shownas bifurcated .atv its lower end to, give it a broad hearing or support,and having one arm extended down below its pivot axis to bear against aspring 15, which tends to throw inward the upper end of the lever.Threaded or screwed through lever 13 a short distance above its pivot.axis, is an adjusting screw 14 which is held in contact with the outerend of rod 2orwith its cap sleeve 2 by the pressure of spring 15 urginglever 13 in-' :therewith.-.: To afford a broad bearing for the lever19Yagainstthe diaphragm 17, its arms carry at their lower ends a disk orhead 19 of circular outline, the bearing face of-whi'ch is made convexas is usual in such instruments. Contact of the convex disk 19 with thediaphragm is maintained by a spring 21 interposed between casting 6 andthe upper end of lever 19, said spring being placed under compression.Its ends are seated in sockets or depressions in frame 5 and lever 19 toinsure its retention in place.

The three-Way valve 16 is of the quick throw or snap action type, and isactuated by vibration of frame or lever 19, which carries at its upperend a confined. coil spring 28, which riding over a spherical head 29 ofthe valve stem and being thereby expanded on passing the center of thespherical head of the valve stem, suddenly contracts and expels saidhead 29, moving it sharply away from the annular spring in a directionopposite to that in which the lever moves. This and equivalent quickthrow devices are illustrated and described in my prior patents abovenoted, and require no further explanation here. So, too, the functionand mode of'operation of the threeway valve 16 being well understood andfully set forth in Patent No. 924.235 to Warren S. Johnson, need not bedescribed at any length. The throw or play of frame or lever 19 islimited by a stop-serew 22. shown in Fig. 2, but omitted in otherfigures to avoid confusion. 9

Figs. 4 and.5 show that portion of the structure which embodies myinvention. It consists of a chamber formed by two circular members 30and 31. each having a circumferential flange, the two flanges beingthreaded and screwed together to form a closed air chamber to which airis admitted through a port or passage 32 connnunicating with thecentralair passage 27 of casting 6. which passage also communicates with thechamber containing diaphragm 17. The member 30 is provided with athreaded neck or nipple by which it is screwed into a correspondinglythreaded socket in the casting 6 in the position indicated in Figs. 1, 2and 3. Between the radial face of the flange of member 30 and an annularshoulder of the flange of member 31, is clamped a flexible diaphragm 34,which when not opposed by superior force is bowed or urged inward ortoward the airport 32 by a light spring 35. or by its own resilience ifthe diaphragm be made of resilient material.

36 indicates a leak port tube the inner end of which is provided with alixcd flange or collar 37 and a nut 38 which screws upon the rear end ofthe tube 37, to clamp and bind between it and the collar 37 thediaphragm 3-1, said diaphragm having a central opening to receive theleak port tube. The joint or connection between the leak port tube-andthe diaphragm is, by the construction described, made air-tight. Thetube 31) is longitudinally movable through a thread ed housing or nipple39. screwed centrally into the cap member 31 of the diaphragm chamber.The housing or nipple 39 is provided at its forward or outer end with acircular disk, the circumference of which maybe milled to facilitate itsturning to adjust it with reference to the chamber 3031. If preferred,holes will be drilled in the face of the disk to receive a pin by whichto turn it. The face of said disk is graduated at its outer edge, thegraduations being read in connection with a stationary pointer 40carried by cap member 31 or other convenient support. The function ofthe housing or nipple 39 is primarily to con' stitute a stop to limitthe outward movement of the leak port tube 36, its inner end being inthe path of and arresting the collar 37 of said leak port tube. Theinward movement is limited by the wall of member 30, which as shown hasa raised central boss grooved to prevent-sealing of the leak tube.

When pressure fluid is admitted to the chamber 30-31 and the leak porttube is sealed, pressure is exerted upon the diaphragm 34 sufficient toovercome the resistance of spring 35, and to move the diaphragm andwithit the leak tube 36. forward or outward. When, however, the leakport is unsealed, air escapes through said leak port to the atmosphere,permitting the spring 35 to collapse or how inward the diaphragm, and tocause a backward or rear ward movement of the leak port tube.

The cap member 31 is provided with a vent 41 to the atmosphere, topermit free movement of the diaphragm and leak port tube. 1 l

Carried by the leak port tube 36 is a bracket 42 to which is pivoted, orfrom which is suspended, a lever or bar 43 carrying a sealing disk orpad 44, preferably of patent leather, celluloid, or like material, whichfaces the end of leak port tube 36 and serves when; pressed against theend of said tube, to seal the leak port therein. A light spring 45carried by the bracket 42 bears against the bar or lever 43, and tendsto pressand hold the valve disk or pad in sealing contact with the leakport tube.

The operation of the device is as follows, reference being had to Figs.3, 4 and 5:

Air or other pressure fluid enters at 7, passestothe three-wayvalve 16by way of passage 24, and by way of passage 25 to restricted passage 26,through said passage.

26 to the main passage 27, and by the latter passage to the chambercontaining diaphragm 17. By a passage-23 opening out of the main passage27 and communicating with port 32 (Figs. 4. and 5), air also enters thechamber containing diaphragm 34. l:he leak port of tube 36 is ofgreatercapaclty than the restricted passage 26, hence when open permitsair to waste or escape more rapidly than it can be supplied to thechamberscontaining diaphragms 17 and 34, and

&

shown in Figs. 3 and 5, and the valve or device to becontrolled andwhich is piped to the three-way valve chamber at 8, will remain open.Upon a riseo-f temperature in the medium surrounding tube 1 (Figs. 1 and3), said tube lengthens, and as rod2 expands or lengthens more slowly,it will be forced back into the tube by. spring 4, screw 14 followingand continuing to bear upon the outer end of rod 2 or its cap sleeve byreason of the action of spring 15 upon the short arm of lever 13, thefree upper end of which latter likewise moves inward.

As best shown in Figs. 3 and 5, the upper end of lever 13, which isbrought to the form of a point or knife edge, stands directly in rear ofand bears against the inner or rear face of bar 43 which carries theport-sealing valve disk orpad 44, and so long as the temperature remainsbetween the normal or mid-point and a predetermined maxii'mun, holdssaid bar 43 slightly away from the outer end of the leak port tube 36against the pressure of spring 45. When, however, by reason of expansionof the tube 1, occa sioned by rise of temperature, the free end oflever13 moves inward, bar 43 with its valve disk or pad 44 will follow underthe force of spring 45, until the pad or disk rests against the end ofthe leak port tube and seals the port. "When this occurs pressure willbuild up in the chambers containing diaphragms 17 and 34, and diaphragms17, acting through lever or frame 19 and moving its upper endinward,will cause a quickthrow of the three-way valve 16 to position to cut offthe supply of pressure fluid to the valve which iscontrolled by theinstrument and supplied by the pipe connecting with boss 8. Diaphragm 34will continue to move until collar 37 of the leak port tube encountersthe inner end of nipple 39, by which time the bar or lever 43 will becarried forward clear of the upper end of lever13, leaving a gap as seenin Fig. 4.

Upon a fall of temperature from the pre determined maximum, contractionof tube 1 will force rod 2 longitudinally outward, and by reason. of itsforward end bearing against screw 14 of lever 13, will cause the free.upper end of said lever to move also. Lever 13 must, however, moveacross the gap between its free end and bar or lever 43 {before it canact to unseat or move away the valve or disk 44 from the leak portoftube 36. The width or extent of this gap is regulated by adjustment ofthe nipple 39, andmaybe made greater or less according to the range oftemperature desired between the opening and closing points. When theleak port tube is moved outward the dis-' tance predetermined by,adjustment of the nipple, be that distance greater or less, theunsealing will occur, and reversal of action will follow promptly.Heretoforethermostats designed to work over a range of a' ing andunsealing of the leak port is insured by the sensitive thermostatelement.

In Fig. 7 the leak port tube 36 is shown screwed into or carried by anupright bar 46 fulcrumed at its lower end in brackets 47 formed upon thecasting 6, said bar being urged inward or toward frame 6 by a lightspring 48. The upper end of the bar 46 encircles or straddles a threadedstem-49 projecting from the front of frame 6, and plays between an innerstop-nut 50 and a milled outer nut 51, which latter may be adjusted asdesired to limit and determine the outward movement of bar 46, andconsequently of leak port tube 36. A finger 52 carried by the bar 46 orother support and projecting in front of the outer face of nut 51registers with graduations' on the face of said nut, and constitutes anadjusting scale similar to the circular disk and pointer 40 of the otherfigure. The valve disk or pad 44 is carried by a bar or lever 43*"-,fulcrumed in ears or brackets 53 formed upon the lever 13, and its freeend is drawn toward the leak tube 36* by'a light spring 54. Said bar orlever 43 hence moves with bar or lever 46 and with leak port tube 36,and maintains 'a fixed relation thereto except for the outward movementoccasioned by lever 13, and the counter movement produced by spring 54.There will hence be no change in angular relation of the valve disk orpad 44 to the leak port nipple and port, and the pad will always seatsquarely and perpendicular to the axis of the leak 'port' tube.

Adjusting screw 14' carries a radial arm 55 which moves over a graduatedplate or scale 56 so that the screw may be accurately adjusted todetermine the initial position of lever 13 relative to the bar or levercarrying the port-sealing pad or closure.

lVhile I have herein shown and described flexible diaphragms for theseveral fluid pressure motors, it is of course to be understood that theinvention contemplates the use ofpistons, these being recognized in theart. as the equivalent of diaphragms, and.

used interchangeablytherewith. The claims are hence to be read with thisunderstanding.

Other variations in the manner of mounting the valve or pad-carrying baror lever will readily suggest themselves to the skilled mechanic, andare within the purview or scope of this invention, -whicl1 consistsbroadly in so mounting the valve or padcarrying element as that it shallmove with the leak port tube or member, and hence be unaffected as toits relation. by the movements of said leak port tube.

Having thus described my invention what I claim is 1. In a controldevice of the leak port type, the combination with a movable leak portmember of a closure for said port responsive to atmospheric conditionsand bodily movable with said leak port member. v

2. A control apparatus of the character described, comprising a movableleak port member; stops limiting and determining the range of movementof said member; and a closure for the leak port responsive toatmospheric conditions and bodily movable with the leak port member.

3. A control apparatus of the character described, comprising a movableleak port member; an adjustable stop for limiting the outward moven'ientof said member; and a closure for the leak port responsive toatmospheric conditions and bodily movable with the leak port member.

4. A control instrument of the character described, comprising a leakport member; a bracket attached to and movable therewith; a bar or leverpivotally attached to said bracket and having a pad or disk facing theport of the member; and a spring tending to move the valve disk or padtoward the port of said leak port member.

A control instrument of the character described, comprising, incombination, a leak port tube or member bodily movable; an adjustablestop to limit and determine the range of movement of said member; abracket mounted upon and movable with said member; a bar or leverpivotally attached to said bracket and provided with a disk or padadapted to seal the port of said leak port tube or member; and a springextending from the bracket to the pad-carrying bar or lever, and tendingto press the latter toward the port of the leak tube or member.

6.'The herein described control instrument, comprising a body or baseprovided with supply and delivery ports and with a quick-throw valve; aleak port tube connected with and movable by a diaphragm subject tofluid pressure; a bracket connected with and movable by said leak porttube; a lever carried by said bracket and provided with a valve or padadapted to close the port in said leak tube; a lever fulcrumed upon themain frame or base of the instrument and adapted to engage by its freeend and to actuate the Valve or pad-carrying lever; a spring tending tomove the actuating lever away from the pad or valvecarrying lever; and amember responsive to atmospheric changes, serving to move the proximityto said graduations; and a 010- aetuating lever in opposition to saidspring. sure for the leak port bodily movable with 7. A controlinstrument of the character the leak port member. 10 described,comprising a movable leak port In testimony whereof I have signed my 5member; a stop limiting and determining name to this specification.

the outward movement of said member and provided with graduations; apointer in CHARLES L. FORTIER.

Eopies of this patent may be obtained for five cents each, by addressingthe Commissioner of Eatents Washington, D. G,

